Bone Maiden

Blending Corpse: The Bone Maiden's proficiency to stealth is doubled while hiding with corpses and can use the hide action around corpses while not in view. While hiding among corpses, the Bone Maiden is considered a trap.

Separation Cull: The Bone Maiden can separate up to 3 sections of itself, 3 20ft. long sections, and each act individually of each other at equal parts reduced health and reduced attacks. 

Bone Cage: When the Bone Maiden successfully grapples a creature. the Bone Maiden can make a free action to attempt to restrain the creature with advantage.

Maiden's Embrace: a creature restrained by the Bone Maiden takes a d8 of piercing damage upon being restrained, at the beginning of restrained creature's turn, or any time the restrained creature takes damage from any source other than from this trait.

Hunter's Stride: This creature ignores non-magical difficult terrain that impedes movement and has a climbing speed and swimming speed equal to movement speed.

 Elongated Form: this creature can extend its' body upward up to 40ft up into the air.

 Room for Many: The Bone Maiden is capable of grappling and restraining 1 large creature, up to 3 medium sized creatures, 5 small creatures, and/or 10 tiny creatures.
1 medium = 2 small = 4 tiny (use this to if want to avoid size semantics)

3 actions, for grapples only

Trap Actor: while the Bone Maiden is hidden among corpses, they can make a grapple check to any creature that moves within 10ft. of it.